remember the roller skates we had when we were younger that would fit over our tennis shoes, and we'd turn a key to tighten them to our shoes?

has anyone ever seen anything like that for putting bike cleats on a pair of running shoes?

i want to put a pair of bottom-of-the-line spd clipless pedals on my spinner at home, but i don't want to have to go out and buy yet another pair of shoes to hold the cleats (and another pair for my wife, whose bike it actually is). right now, i've got toe clips, and in fairness, they work just fine, but for long sessions, i'd rather have something more comfy.

any ideas? if not, anyone want to invent it and give me the credit (and half the revenues)?